Engine/Transmission (1998.5 - 2002) Lift pump hard start question help

[gottorq33]

Question when friend at dodge replaced vp44 star had him do the flow test to see how much fuel in a specific time he said I was way above. My question is with my fuel setup even if the stock lift pump was getting weak or was working intermittent would the pusher pump at the back still flow enough fuel to start engine could this be my hard starting issue if stock lp is going south my pressures are 19 to 20 idle 15 cruise and 8 or 9 WOT i know if the pusher died it would act as a block and would not allow fuel flow to pump but this whole hard starting (sometimes) issue is getting the best of me

 

[Marco]

I've just repalced the pusher setup with a FASS.



My setup was going slowly. First the FP was about 9 PSI at idle then 5 then zero... I know for sure that the pusher survived the lift pump a few weeks.



So yes, the pusher will get enough fuel up to the VP to start and run the engine. More, my engine always started and run even whith both pumps dead. Sure I was very easy on the throttle!



I then replaced the pumps with an electric pump I use in my boat to transfer fuel. ( Waiting for the FASS to arrive) That thing would pump out 45 Psi. Never a hard start with this one too.



From my experience I can tell you that FP does not cause hard starts.

Maybe I'm just one lucky dude?



Marco

 

[tractorface]

Bad thoughts

Wonder if your VP is dying again? I went nuts looking for air leaks, turned out to be the VP. Would love to know what the fuel stream looks like from your rig. Could be pulsing do to collapsing valve in tank suction line, this would not be nice for VP's. Your moving a lot of fuel an should be pushing the limits of what the stock fuel module may be able to supply. I have one in the garage if you want to stare at it. After staring at it a while I wonder how much (little) fuel it is capable of flowing. Also it is very easy to see how some would be worse than others.

Also heard that high fuel pressure at start up can cause your problem. I had a hard start one day after installing my new VP, I had a fuel leak in the return line, tightened it up and have had no problems since. Can not figure out why leak in return would matter but that does not mean it doesn't.



Last thing is maybe your overflow valve is sticking open on occasion causing your VP to loose prime. I have a new one in the garage if you want to try it. Pretty simple and probably not your trouble but... ... .

 

[gottorq33]

hey tractorface I sent you a PM will take you up on offer or maybe you can see something i am missing give me a shout thanks